1, 3-diaryl and 1, 3, 5-triaryl-pyrazoline derivatives



FIP'8309 3,135,742 LZi-BHARYL AND1,3,5-TRIARYLPYRAZOMNE DERTVATHVE Annemarie Wagner, Lever-liaison, Anton Schlachter, Lochham, near Munich, and'lljierhert Marzolphborrnagen, Germany, assignors to Farheniabrilren Bayer Alrtlengeseiisclrait, Leverlniscn, Germany, a corporation of Germany No Drawing. Continuation of application Ser. No. 642,356, Feh. 26, 1957. This application May 15, W62, Ser. No. 194,9?9

Claims priority, application Germany Mar. 3, 1955 3 Claims. (Cl. 260-232 9} The present invention relates to brightening agents; more particularly it concerns brightening agents of the 1,3- diarylor 1,3,5-triaryl-pyrazoline series.

It is known to use bluish fluorescent 1,3-diarylor 1,3,5-triaryl-pyrazoline compounds which contain at least one sulfonic acid group, possibly in addition to a great variety of other substituents, for brightening fibrous materials, film and the'like, cf. for instance U.S. patent specification No. 2,639,990 or French patent specification No. 1,093,063.

it has now been found that even better brightening effects are obtained by using as brightening agents bluish fluorescent 1,3-diarylor 1,3,5-triaryl-pyrazoline compounds which contain at least one sulfonamide group, possibly in addition to other appropriate substituents such as for instance halogen, alkyl or alkoxy groups, the sulfonamide group being unsubstituted or partially or wholly substituted by alkyl or aryl radicals. The 1,3- diarylor 1,3,5-triaryl-pyrazoline compounds which contain a sulfonamide group in the para-position of the aryl radical linked to the nitrogen atom have proved to be especially useful.

The 1,3-diarylor 1,3,5-triaryl-pyrazolines to be enployed as brightening agents according to the invention containing at least one sulfonamide group, may be produced by various methods, for example by the action of ammonia or'amines on the corresponding aryl-pyrazolinesulfonyl chlorides. The production of the proposed brightening agents may also be carried out in a manner analogous to the known production of aryl-pyrazolines from aryl-hydrazines and a,B-unsaturated aryl ketone's or from their addition products with ammonia, amines, hydrogen halides or alcohols, from the corresponding starting components containing'sulfonarnide groups.

The proposed brightening agents may beused in conventional manner at room temperature or at elevated temperatures. If the brightening agents are water-soluble, it is advisable to use them in the form ofan aqueous solution, if they are water-insoluble, they may be employed in the form of aqueous dispersions, possibly with the aid of dispersing agents. They may also be used in the form of solutions in organic solvents. The proposed brightening agents, particularly the compounds which are barely soluble in water, may also be incorporated in casting or spinning melts or solutions used for the production of synthetic articles such as foils, fibres of filaments. The quantities required for brightening may vary within wide limits; they can readily be established by preliminary experiments.

The brightening agents to be employed according to the invention are suitable for brightening a great variety of materials such as textile fabrics, paper, leather or soaps. They are especially suitable for brightening wool and synthetic fibres, particularly in combination with washing f'T-E EFEREliCE agents. Thebrightening effects obtained possess good fastness to light. Compared with the previously known aryl-pyrazolines containing sulfonic acid groups, the aryl pyrazolines of the present invention which contain sulfonamide groups exhibit improved brightening elfects, especially on synthetic fibres, particularly when applied in a neutral bath;

A very advantageous embodimentof the present invention consists in adding the proposed brightening agents to casting or spinning masses which contain acrylonitrile polymers or copolymers. The filaments, fibres, foils or other articles which can be produced in known manner from these casting or spinning masses mixed with the brightening agents of the invention exhibit a brightening effect which has heretofore never been obtained in articles containing acrylonitrile polymers or copolymers and which is excellently stable to light and washing.

The following examples serve to illustrate the invention without, however, limiting the scope thereof; the parts given by weight.

Example 1 Laundry goods consistiiig of polyamide fibres, acetate rayon and wool, and exhibiting a yellowish appearance, are washedin the usual manner witha suitable washing powder combination which contains 0.1 percent of 1-psulfonamidophenyl 3 p-chlorophenyl-pyrazoline. Even after washing-only once, the articles treated show a purewhite appearance. i

The l p-sulfonamidophenyl-S-p-chlorophenyl-pyrazoline having a melting point of 218 C. was prepared from p-chlorophenyi-fl-chloroethyl ketone and p-liydrazinebenzene-sulfonamide' in methanolic solution in the pres ence of pyridine.

Example 2 Laundry goods of cellulose fibres, polyamide fibres, acetate rayon and wool are washed at a temperature of about 40 C. with a conventional household washing agent which contains (possibly in addition to oxygenyielding compounds) 0.05 percent of l-p-sulfonamidophenyl 3 p-bromophenyl-pyrazoline. The brightening agent, in contrast to other brightening agents, for example those based on amino-stilbene-disulfonic acids, does not go on cellulose-containing fibres in the first instance, but mainly on the laundry goods made of polyamide fibres, acetate rayon and wool, so that these show an excellent brightening effect. The lesserafiinity for cellulose fibres may be of advantage, when cotton articles having delicate pastel shades are washed at the same time with other goods; thus no undesirable change of colour will occur.

The brightening agent used having a melting point of 220 C. was prepared from p-brornophenyl-fl-chloroethy] ketone and p-hydraZine-benzene-sulfonamide.

Example 3 10,000 parts ofcurd soap, soapneedles and soap flakes are intimately mixed with one part of 'rl-p-sulfonamidophenyl-3-p tolyl'-pyrazoline at any time during their manufacture. The soap products having intially a yellowish appearance obtain in this manner a pure white appearance.

The brightening agent usedhaving a melting point of 257 C. was prepared from p -tolyl-B-chloro-ethyl-ketone and p-hydrazino-benzene-sulfonamide.

7 Example 4 7 10,000 parts of soap based on fatty acids or synthetics ShiiiiCi'i iillilh'i or mixture of both types are intimately mixed with about parts of 1-p-sulfanilidophenyl-3-p-chlorophenyl-pyrazoline. The soaps thus obtained show an excellent brightening effect. Laundry goods of polyamide fibres, acetate rayon or wool washed with these soaps also show an excellent brightening effect. It should be noted that none of the effects known as colour accumulation occurs, even if the soap is constantly used.

The 1 p sulfanilidophenyl 3 p chlorophenylpyrazoline was prepared from l-p-sulfanilidophenylhydrazine and p-chlorophenyl-B-chloroethyl ketone; the melting point is 202 C.

Example 5 10,000 parts of a soap base siutable for the manufacture of toilet soaps are treated in a mixing apparatus, prior to working up in a soap mill, with 3 parts of the brightening agent described below. During this process, other customary ingredients such as perfumes, anti-oxidants, deodorants or white pigments, may also be added to the soap. A pure-white appearance is thus imparted to the intiially pale cream coloured soap. When colours are also employed, the shades become clearer and more brilliant.

The brightening agent empoyed was prepared in the following manner:

30 part of 1,3-diphenyl-pyraz0line were added with cooling to 70 parts of chlorosulfonic acid, after the mixture was allowed to stand at room temperature for one hour, it was poured onto ice. The 1,3-diphenyl-pyrazoline-sulfochloride thus separated was filtered off with suction. 7 parts of the 1,3-diphenyl-pyrazo1ine-sulfochloride thus obtained were then boiled under reflux with 6 parts of N-methylaminoethane-sulfonic acid in 70 parts of acetone. Thereupon, 1,3-diphenyl-pyrazoline-sulfomethylaminoethane-sulfonic acid separated out as a light yellow powder.

Example 6 When rinsing laundry goods of olyamide fibres, acetate rayon and wool, 0.02 gram per litre of the brightening agent 1-p-sulfonamidophenyl 3 p methoxy-phenylpyrazoline of M.P. 228 C. obtainable from p-methoxyphenyl-B-chlorethyl ketone and p-hydrazine-benzene-sulfonamide is added to one of the rinsing baths. The brightening agent may be used directly or in compounded form, i.e. as a tablet or powder, in admixture with complex phosphates, Glaubers salt, bicarbonates or the like. After a short time, if necessary with slight agitation of the goods in the rinsing liquor, the non-coloured laundry goods of the above-mentioned types of fibre become pure white through the action of the brightening agent, whilst the colours of the laundred articles become more brilliant.

Example 7 Polyamide fibres, acetate rayon, wool or silk bleached in conventional manner are impregnated with a liquor containing 0.05-0.2 gram per litre of l-p-sulfonamidophenyl-3,S-diphenyl-pyrazoline as brightening agent; the liquor may also contain cation-active softening and finishing agents. The fabrics are then dried. The white shade of the goods thus obtained is distinctly brighter and more brilliant than that obtained without the use of the brightening agent.

The brightening agent employed having a melting point of 209 C. may be prepared from benzal-acetophenone and p-hydrazino benzene-sulfonamide in alcoholic acetic solution.

' Example 8 The brightening agent described below is dissolved by pouring boiling water over it; sufl'icient of this solution is then introduced into an aqueous bath for brightening wool or polyamide fibres that the bath, using a liquor-t0- goods ratio of 40:1, contains 0.03-3 percent of the brightening agent referred to the weight of the goods. Prep-hydrazinobenzene-sulfonic viously, 3-percent of formic acid (85%) was added to the bath. The pre-wetted textile material is then placed in the bath at about C.; the bath temperature is now slowly increased to 50-60 C. and the textile material is moderately agitated in the liquor at this temperature for about 20 minutes. The textile material thus treated is very well brightened.

The brightening agent employed is l-p-(sulphonyl-fimorpholino ethylamido) phenyl 3 p chlorophenylpyrazoline prepared from p-chlorophenyl-[3-chlorethyl ketone and p-hydrazino-benzene-sulfonic acid-,H-morpholinoethyl-amide.

The same result is attained if 1-p-(sulfonyl-y-dimethylamino-propylamido)-phenyl-3-p-chlorophenyl pyrazoline is used instead of the aforesaid brightening agent. It is obtainable from p-chlorophenyl-fl-chlorethyl ketone and acid-y-dimethylamino-propyl-amide.

Example 9 Greyish white or undyed textiles of polyamide fibres, acetate rayon or wool, which have turned somewhat yellow in storage or possibly in use, are treated at 4050 C.

for 15 minutes at a liquor-to-goods ratio of 1:20 with an aqueous reducing bleaching solution containing per litre 2 grams of sodium hydrosulfite, 1 gram of tetrasodium pyrophosphate, 0.5 gram of a wetting and dispersing agent of the alkyl-naphthalene-sulfonate type, and 0.02 gram of 1 p sulfonamidophenyl 3 m,p dichlorophenyl pyrazoline. After rinsing and drying, the textiles thus treated exhibit an improved and more brilliant white than those treated with the same reducing bleaching liquor, but without the pyrazoline brightening compound. Polyacrylonitrile fibers may also be brightened in the same manner, but in this case higher temperatures up to about 100 C. are more advantageous.

The aforesaid pyrazoline compound serving as brightening agent and having a melting point of 233236 C. was obtained from m,p-dichlorophenyl-B-chlorethyl ketone and p-hydrazino-benzene-sulfonamide.

Example 10 In 750 parts of dimethyl formamide are first dissolved 0.25 part of 1-p-sulfonamidophenyl-3-p-chlorophenyl-pyrazoline, prepared from p-chlorophenyl-fi-chlorethyl ketone and p-hydrazino-benzene-sulfonamide in methanolic solution in the presence of pyridine, and then 250 parts of polyacrylonitrile of K-value with heating and stirring. The solution thus obtained is then spun in usual manner according to the dry-spinning process so that the filaments after stretching in soiling water by 300 percent have a titre of about 3 denier. The filaments thus obtained are pure white in diffuse daylight, whilst filaments prepared in a comparable manner without the addition of the brightening agent exhibit a yellowish white shade.

If pigments or soluble dyestuffs are added in addition to the brightening agent, filaments are obtained, the colour of which is distinguished by great brilliancy.

This application is a continuation of our application Serial No. 642,356, filed February 26, 1957, now abandoned.

We claim:

1. A fluorescent pyrazoline compound of the formula I SOz-Z wherein X is a member of the group consisting of phenyl,

halogen-phenyl, lower alkyl-phenyl, and alkoxy-phenyl; 2. 1-p-sulfonamidopheny1-3-p-chlorophenyl-pyrazoline. Y is a member of the group consisting of hydrogen and 3. 1 p (sulfonyl 'y dimethylamino pr0py1amid0)- phenyl, and Z is a member of the group consisting of phenyl-3-p-chlorophenyl-pyrazoline.

NH, 3 5 References (iited in the file of this patent \CH2CH2SOaH 9 6 95 UNETED STATES PATENT?VI 21 1961 2, ,2 a1. NHCH CH N W 7 P ue FOREIGN PATENTS and 10 CH8 1,019,449 France Oct. 29, 1952 

1. A FLUORESCENT PYRAZOLINE COMPOUND OF THE FORMULA
 2. 1-P-SULFONAMIDOPHENYL-3-P-CHLOROPHENYL-PYRAZOLINE. 